Don't be fooled, xiaohan marks China's coldest day of the year!

Time to walk on ice! Xiaohan, or Minor Cold, which coincides with sanjiu — the third "nine days" after Winter Solstice — is marked by revelry when people take to the water — literally!

Xiaohan usually arrives on January 4-6, when the sun's elliptical longitude reaches 285 degrees. This year, it falls on January 4to mark China's coldest period of the year, perfect for venturing outdoors for a walk on icy cold river.

The average temperature in north China drops below zero degrees Celsius, while the lowest temperature in some regions will be minus 40 degrees. The regions in south of the Yangtze River are relatively warmer with an average temperature around 5 degrees Celsius, but it also drops below zero degrees when cold air invades from the north.

Regardless of the cold weather, yang (warm) energy is believed to sprout around Minor Cold. A Chinese proverb describes the days after xiaohan as the "three periods of waiting" — waiting for the wild geese to set off for the north, waiting for the magpies to start building nests and waiting for the pheasants to sing and mate.

To ensure a good harvest, farmers are usually busy protecting crops like covering the earth with plant ashes, straws or green houses — all that blossom in spring.

It is also important for people to keep warm in the coldest days. Besides causing cold-related respiratory problems, the freezing weather can lead to relapse of joint pains, cervical spondylosis and cardiovascular diseases due to insufficient blood and energy circulation.

TCM physicians suggest wearing a hat when going out to protect the yang energy. Keeping the belly and joints warm are equally important to protect the body from cold-related diseases. Soaking feet in hot water regularly can also help boost blood and energy circulation during the chilly days.

Though most plants wither, wintersweets blossom around Minor Cold days and plum buds are ready to burst, ensuring that it is the time to appreciate flowers.

With fields covered by snow and rivers frozen in north China, local residents venture out for skiing, ice-skating and ice sculpture.

There is also the tradition of laji (winter sacrifice) in the 12th month of Chinese lunar calendar. Ancient Chinese would offer livestock as sacrifice to the ancestors and gods, and pray for a good year ahead. The preparation for Winter Sacrifice often starts as early as the Minor Cold day.

Mutton hotpot, chestnuts roasted with brown sugar and baked sweet potatoes are popular food that help to keep people warm in the cold days.

In different regions there are different Minor Cold dishes.

Sticky rice

Having a bowl of sticky rice on the morning of Minor Cold is a tradition in Guangzhou, capital city of Guangdong Province. The dish is made up of 60 percent sticky rice and 40 percent rice.

Fried preserved pork, sausage and peanuts are usually chopped and mixed in the rice to enrich flavors.

Rice with vegetables

Caifan, literally rice with vegetables, is a popular dish in Nanjing, capital city of Jiangsu Province. Apart from green vegetables and rice, the common ingredients for a typical Nanjing caifan includes sticky rice, ginger slices, preserved pork slices, sausage slices and dried salted duck.

Eggs and chicken soup

Some elderly residents in Nanjing also follow a tradition of eating eggs every day and chicken every nine days after Winter Solstice.

Chicken soup with reinforcing herbs like jujube, wolfberry, longan, yam or cordyceps flowers are especially popular among people.

Mutton soup

Having a bowl of hot mutton soup is believed to be the best defense against cold weather in China.

Mutton, as a "warm" food according to TCM, helps to boost the yang energy and protects the body against the chill.

Cooking the soup with supporting herbs like angelica and ginger improves immunity and relieves chronic fatigue.